Safety improvement for a fuel tank

ABSTRACT

A fuel tank is improved by the addition of a filler of metallic mesh, the addition of an outer sleeve of fuel and vapor impervious, fire resistant, thermoplastic material, and the fuel line outlet cover is secured against release due to collision. A method of improving a fuel tank includes the securing of the fuel line outlet cover, the addition of the outer sleeve and the installation of the tank into the vehicle. Finally, a tank assembly is described which includes a tank enclosure, the sleeve surrounding the enclosure, a reinforced fastening of the fuel line attachment cover to the tank enclosure, and a filler of explosion suppressing metallic mesh positioned within the tank.

CROSS REFERENCE TO RELATED APPLICATIONS

Not Applicable

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to fuel tanks, such as are currently in use with automobiles. More particularly, this invention relates to a safety improvement in these tanks which reduces the risk of fire and explosion of the tank when the vehicle is involved in a collision.

2. Description of the Prior Art

Recently fuel tanks installed in automobiles have shown a tendency to lose their structural integrity when the vehicle is involved in a collision, allowing dangerous leakage of fuel and fuel vapor. This leakage is due in part to cracks or breaks in the wall of the tank and due in part to the separation of the fuel line attachment cover from the tank wall. Regardless of the source of the leakage, a catastrophic fire and explosion is often the result.

Prior art explosion suppression apparatus has included the use of a metallic mesh insert, as described in U.S. Pat. No. 6,604,644 and U.S. Pat. No. 6,415,942. Such systems effectively suppress explosion when an un-ruptured tank is in contact with a fire, but they do not inhibit the spilling of fuel from a tank rupture or the venting of fuel vapor. Consequently, the risk of fire and explosion still persists with prior art tanks.

SUMMARY OF THE INVENTION

It is accordingly the principal object of this invention to improve the safety of vehicle fuel tanks and reduce the risk of fire or explosion when a vehicle is involved in a collision.

This and other objects are accomplished by covering the tank exterior with a sleeve of fuel and vapor impervious material. Preferably, before the application of the sleeve, the fuel line attachment cover is secured against collision caused detachment from the tank by the addition of fastening screws. In a further aspect of the invention, a filler of metallic mesh is placed within the tank such that it substantially fills the interior of the tank and serves to suppress explosion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a stock prior art automobile fuel tank depicting its metal wall enclosure, the fuel line, and the fuel line attachment cover.

FIG. 2 is a perspective view of the stock automobile fuel tank of FIG. 1 depicting the removal of the fuel line and the fuel line attachment cover.

FIG. 3 is a perspective view of the automobile fuel tank of FIG. 2 showing the reattachment of the fuel line attachment cover with additional fastening screws.

FIG. 4 is a perspective view of a portion of a sheet of expanded metallic foil for use as the mesh filler insert within the tank.

FIG. 5 is a perspective view, shown partially cut away, of the improved tank of the present invention showing filler packets of metallic foil mesh within the tank and showing a sleeve applied around the tank exterior.

FIG. 6 is a perspective view, shown partially cut away, of the improved tank of the present invention showing a filler of metallic foil mesh within the tank and showing a sleeve applied around the tank exterior.

While the invention will be described in connection with a preferred embodiment, it will be understood that it is not the intent to limit the invention to that embodiment. On the contrary, it is the intent to cover all alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning first to FIG. 1 there is shown a prior art fuel tank 10 comprised of an enclosure wall 12, typically of a metal composition. Also shown is a fuel line 14, affixed to the tank enclosure 12 by means of a fuel line attachment cover 16. This prior art fuel line attachment cover 16 is typically affixed to the tank enclosure 12 by screws 18.

According to one aspect of the present invention, the fuel line 14 and the fuel line attachment cover 16 of the prior art fuel tank are first removed, as depicted in FIG. 2, and then reinstalled, as shown in FIG. 3. During the reinstallation of the attachment cover, additional fastening means is applied, such as additional screws 20, or the like, to further secure the cover 16 and thereby prevent detachment during a collision.

In another aspect of the present invention, a filler for the tank is formed from one or more sheets of expanded metallic sheet 30, a portion of which is shown in FIG. 4. These metallic sheets are preferably an aluminum mesh and are now well known in the art as an explosion suppressing filler for tanks of combustible fuel (See for example U.S. Pat. No. 6,604,644 and U.S. Pat. No. 6,415,942). These mesh sheets may be formed into packets 35, as described in U.S. Pat. No. 6,604,644, and then inserted into a tank (see FIG. 5) to substantially fill the interior of the tank. Alternatively, as shown in FIG. 6, the mesh sheet may be folded, rolled, or otherwise formed to provide a filler 36 of metallic mesh which substantially fills the tank.

In a further aspect of this invention, the tank is covered with a sleeve 40 of material which is substantially impervious to liquid fuel and fuel vapor (see FIGS. 5 and 6). This sleeve covers the entire tank enclosure 12 and substantially seals the tank to prevent passage of liquid fuel or fuel vapor which may leak from the tank through any crack or opening caused by a collision. This sleeve is preferably formed from a fire resistant thermoplastic material and may be applied to the tank exterior with substantial effect independent of the other improvements discussed herein.

The above described tank modification has been directed toward new stock tanks, prior to installation in a vehicle. When a used tank from a vehicle is being modified as herein described, the tank is first removed from the vehicle and drained of fuel prior to modification. It is then modified as above described and reinstalled into the vehicle.

From the foregoing description, it will be apparent that modifications can be made to the apparatus and method for using same without departing from the teachings of the present invention. Accordingly, the scope of the invention is only to be limited as necessitated by the accompanying claims. 

1. A method for improving the safety of a vehicle fuel tank having an exterior surface defined thereon, an interior defined therein, and a fuel line attachment cover attached to the tank, the method comprising the step of: covering said tank exterior surface with a sleeve of material that is substantially impervious to fuel and fuel vapor.
 2. The method of claim 1 further comprising placing within said tank interior a filler of metallic mesh, wherein said filler substantially fills said interior of said tank.
 3. The method of claim 2 wherein said filler is comprised of one or more sheets of expanded aluminum mesh formed into packets.
 4. The method of claim 1 wherein said sleeve is comprised of a fire resistant thermoplastic material.
 5. The method of claim 4 further comprising placing within said tank interior a filler of metallic mesh, wherein said filler substantially fills said interior of said tank.
 6. The method of claim 5 wherein said filler is comprised of one or more sheets of expanded aluminum mesh formed into packets.
 7. The method of claim 1 further comprising the step of adding fastening means to secure the fuel line attachment cover to said tank.
 8. The method of claim 7 wherein said sleeve is comprised of a fire resistant thermoplastic material.
 9. The method of claim 8 further comprising placing within said tank interior a filler of metallic mesh, wherein said filler substantially fills said interior of said tank.
 10. The method of claim 9 wherein said filler is comprised of one or more sheets of expanded aluminum mesh formed into packets.
 11. A fuel tank assembly comprising: a tank enclosure having an exterior surface defined thereon, an interior defined therein, and having a fuel line attachment cover attached thereto; a sleeve affixed to said exterior surface of said enclosure, wherein said sleeve is substantially impervious to fuel and fuel vapor.
 12. The fuel tank assembly of claim 11 further comprising a filler of metallic mesh positioned within said interior of said tank enclosure, wherein said filler is comprised of expanded aluminum mesh.
 13. The fuel tank assembly of claim 12 wherein said filler is comprised of packets formed from sheets of expanded aluminum mesh.
 14. The fuel tank assembly of claim 11 wherein said sleeve is comprised of a fire resistant thermoplastic material.
 15. The fuel tank assembly of claim 14 further comprising a filler of metallic mesh positioned within said interior of said tank enclosure, wherein said filler is comprised of expanded aluminum mesh.
 16. The fuel tank assembly of claim 15 wherein said filler is comprised of packets formed from sheets of expanded aluminum mesh.
 17. The fuel tank assembly of claim 11 further comprising fastening means affixed to the fuel line attachment cover, wherein said fastening means prevents detachment of said fuel line attachment cover from said tank during a collision.
 18. The fuel tank assembly of claim 17 wherein said sleeve is comprised of a fire resistant thermoplastic material.
 19. The fuel tank assembly of claim 18 further comprising a filler of metallic mesh positioned within said interior of said tank enclosure, wherein said filler is comprised of expanded aluminum mesh.
 20. The fuel tank assembly of claim 19 wherein said filler is comprised of packets formed from sheets of expanded aluminum mesh. 